Air conditioning apparatus



June 13, 1967 G. H. BROWN 3,324,677

AIR CONDITIONING APPARATUS Filed Oct. 7, 1965 2 Sheets-Sheet 2 uHIIIIll United States Patent 3,324,677 AIR CGNDITIONING APPARATUS Gordon H. Brown, St. Joseph, Mich assignor to Whirlpool Corporation, a corporation of Delaware Filed Oct. 7, 1965, Ser. No. 493,621 11 Claims. (Cl. 62-262) This invention relates to apparatus for providing conditioned air and in particular to apparatus for providing conditioned air to a chamber such as a room.

In one form of conventional air conditioning apparatus, blower means are provided for circulating air from the chamber, or room, to be air conditioned through suitable air conditioning means and redelivering the conditioned air back to the room. Such apparatus conventionally includes evaporator means for cooling the air as it is passed therethrough. In certain forms of such apparatus, the airmay be alternatively directed into heat exchange relationship with the condenser portion of the refrigeration apparatus thereby to selectively provide heated air back to the room. Still further, in certain of the known air conditioning apparatuses, means are provided for alternatively exhausting the room air to externally thereof, or for bringing fresh air from externally thereof into the room as desired.

A problem arises, however, in the existing air conditioners of the above described type in that the desired cooling and heating effects are not efliciently provided and undesirable noise and drafts are often produced. The present invention comprehends an improved air conditioning apparatus eliminating the disadvantages of the known apparatuses in a novel and simple manner.

Thus, a principal feature of the present invention is the provision of a new and improved air conditioning apparatus.

A further feature of the invention is the provision of such an apparatus having new and improved means for providing a desired controlled air flow therethrough.

Another feature of the invention is the provision of such apparatus having a pair of air flowing means of different air flow capacity for providing improved balanced air flow therein.

A yet further feature of the invention is the provision of such an air conditioning apparatus for providing conditioned air including heat transfer apparatus having an endothermic portion and an exothermic portion, means defining a heat transfer space including first and second portions, means for disposing the heat transfer apparatus with the endothermic portion and exothermic portion selectively in the first and second portions of the space respectively, and in the second and first portions of the space respectively, and concurrently partially in each of the portions of the space, first means for flowing air from the chamber to the first portion of the space, second means for flowing air from externally of the chamber to the second portion of the space, the second air flowing means being arranged to flow air at a rate substantially greater than the rate at which the first air flowing means flows air, and means for conducting the flowed air outwardly from the first portion of the space to a first location and outwardly from the second portion of the space to a second location.

A yet further feature of the invention is the provision of such an air conditioning apparatus wherein the air conducting means is further arranged for selectively conducting air from the first portion of the space through the second portion of the space to the second location, and from the second portion of the space through the first portion of the space to the first location.

Still another feature of the invention is the provision of such apparatus arranged to utilize a single one of the ice air flowing means for providing movement of air solely from said first location to said second location.

A further feature of the invention is the provision of such apparatus arranged to utilize a single one of the air flowing means for providing movement of air solely from said second location to said first location.

Still another feature of the invention is the provision of such air conditioning apparatus wherein the disposing means is arranged to dispose the heat transfer apparatus selectively for heat exchange relationship with the air in the space or substantially free of heat exchange relationship therewith.

Another feature of the invention is the provision of such air conditioning apparatus including means for removably securing the first and second air flowing means as a unit to the means defining the heat transfer space whereby the apparatus may be provided in separate sections so as to facilitate shipment and installation thereof.

A further feature of the invention is the provision of such air conditioning apparatus wherein the air flowing means includes a housing having means for providing a selectively positionable opening providing communication between the chamber and at least one of the space portions.

Still another feature of the invention is the provision of such air conditioning apparatus wherein the housing defines a top and a side and the opening means is selectively positionable to provide the opening alternatively in the top or side of the housing.

Other features and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawings wherein:

FIGURE 1 is a top plan view of an air conditioning apparatus embodying the invention with an upper housing cover removed for facilitated illustration of the apparatus and with the apparatus installed in association with suitable outlet ducts;

FIGURE 2 is a vertical section taken substantially along the line 22 of FIGURE 1, but with the cover being illustrated therein;

FIGURE 3 is a vertical section taken substantially along the line 3-3 of FIGURE 1;

FIGURE 4 is a reduced horizontal section taken substantially along the line 4-4 of FIGURE 2 and with the apparatus arranged as for providing heated air to the room;

FIGURE 5 is a horizontal section similar to that of FIGURE 4, but with the apparatus as arranged to provide refrigerated air to the room;

FIGURE 6 is a horizontal section similar to that of FIGURE 4, but with the apparatus arranged to permit selectively exhausting of air from the room or delivery of fresh air from externally of the room thereto; and

FIGURE 7 is a horizontal section similar to that of FIGURE 4, but with the apparatus arranged to provide warmed air to the room from externally thereof.

In the exemplary embodiment of the invention as disclosed in the drawing, an air conditioning apparatus generally designated 10 is shown to comprise a housing generally designated 11 including an upper parallelepiped enclosure 12 and a lower parallelepiped enclosure 13. The upper enclosure is divided centrally by an insulated driving wall 14 to define a first blower space 15 a second blower space 16. Air is delivered to blower space 15 from a first location, such as a chamber, or room 17 through an inlet duct 18. Air is delivered to space 16 from a second location, herein the space 19 externally of room 17 through an inlet duct 20.

A first air flowing means, herein comprising a blower 21, is disposed in first blower space 15 and a second air flowing means, herein comprising a second blower 22, is

:53 disposed in second blower space 16 as best seen in FIG- URES l and 2. Blower 21 includes an outlet portion 23 which opens downwardly through a bottom wall 24 of the upper enclosure 12 and second blower 22 includes an outlet portion 25 opening downwardly through the bottom wall 24 as best seen in FIGURE 2.

The lower enclosure 13 is provided with a right side wall 26 defining a discharge opening 27 and a left side wall 28 defining a discharge opening 29 as best seen in FIGURE 1. An outlet duct 30 extends through the opening 27 to open into the interior space 56 within the lower enclosure 13 and an outlet duct 32 extends through opening 29 to open into the space 52. A rotatable platform 33 is provided with a depending pivot 34 received in a suitable socket 35 in the bottom wall 36 of the lower enclosure 13 as shown in FIGURE 2. Upstanding from the platform 33 is a first segmentally cylindrical wall member 37 and a diametrically opposed second segmentally cylindrical wall portion 38 each of which extend in a clockwise direction (as shown in FIGURE 1) from a diametric upstanding dividing wall 39. Continuing segmentally cylindrically from the clockwise end of wall 37 is an upstanding evaporator structure which is substantialy symmetrically arranged about the upright diametric plane perpendicular to the flat plane of the dividing wall 39 thereby to define between the clockwise end of the evaporator 40 and the dividing wall 39 an opening 41. A segmentally cylindrical condenser structure 42 upstands from the platform extending in a clockwise direction from the clockwise end of the wall 38, as shown in FIGURE 1, and is similarly symmetrically arranged diametrically opposite the evaporator structure 40 so as to define between the clockwise end of the condenser and the dividing wall 39 an opening 43. The evaporator 40 and condenser 42 are of generally conventional construction of the type used in refrigeration systems employing a compressible refrigerant fluid. Apparatus 10 includes a compressor '44 which is also mounted on the platform 33, and as best shown in FIGURES 1 and 2, is disposed adjacent dividing wall 39 radially inwardly of the center of the condenser 42.

An outlet connector 45 is carried on the wall 26 to extend from openings 27 into sealed engagement with the condenser 42 when the apparatus is arranged as shown in FIGURE 1. A corresponding connector 46 is carried on wall 28 to extend from opening 29 into sealed engagement with the evaporator 40 when the apparatus is so arranged. As will be brought out more fully hereinafter, the connectors 45 and 46 further sealingly engage the walls 37 and 38 and the opposite one of the condenser and evaporator when the platform 33 is rotated so as to dispose these elements in different positions relative to the upright axis 47 of the pivot 34.

Rotation of platform 33 may be effected in any suitable manner and herein is effected by means of a suitable electric motor 48 driving a chain 49 which in turn engages a sprocket :50 subjacent platform 33. Control of the positioning motor 48 as well as the operation of the refrigeration apparatus and blowers 21 and 22 is effected herein by suitable conventional control means 51 (FIGURE 3) illustratively carried on the upper housing 12, it being obvious to those skilled in the art that any suitable control means may be employed for such control purposes and mounted as desired on the apparatus.

As discussed briefly above, the invention comprehends an improved control of air flow through the apparatus. One of the structural features of the apparatus 19 providing the improved air flow control is the provision of the blower 22 having an air flow capacity substantially greater than the air flow capacity of blower 21. Illustratively, the blower 22 may have an air flow capacity on the order of approximately greater than the capacity of blower 21 (e.g. a capacity of 1800 to 2200 c.f.rn., where the blower 21 has a capacity on the order 4 of 1100 to 1200 c.f,m.). Thus, apparatus 10 is arranged to provide a greater air fiow of the air from space 19, outside air, where space 17 is a room to be air conditioned.

Illustratively, as shown in FIGURES 1 and 4, in the arrangement of apparatus 10 wherein the exothermic heat transfer apparatus, condenser 42, extends across outlet opening 27 leading through duct 30 to the room to be air conditioned, the endothermic heat transfer apparatus, evaporator 40, extends across the opening 29. Air is delivered by the large blower 22 downwardly into the space 52 and thence outwardly through the discharge duct 32. In this position, the dividing wall 39 is sealed to the rear wall 53 and front wall 54 of the lower housing 13 by suitable wipers 55, and the opposite ends of the evaporator 40 are sealingly connected to the left side wall 28 of the lower housing so as to assure full flow of the air from blower 22 through the evaporator 40 to provide maximum heat transfer therebetween. At the same time, blower 21 draws the room air through inlet duct 18 and passes this air downwardly into the space 56 for flow through the condenser 42 and outwardly through discharge duct 30 for delivering the heated air to the room space 17.

Referring now to FIGURE 5, the arrangement of apparatus 10 for purposes of providing refrigerated air to the room space 17 is shown to comprise an arrangement substantially the reverse of that of FIGURE 4. Thus, in FIGURE 5, the platform 33 has been rotated, by motor 48, 180 degrees from the position of FIGURE 4 so as to dispose the endothermic evaporator 40 across the outlet opening 27 and the exothermic condenser 42 across the outlet opening 29. The compressor 44 is now disposed to the left of the dividing Wall 39 and in this arrangement the compressor and condenser are disposed in space 52 to which blower 22 delivers the air from inlet duct 20. The evaporator 40 is disposed in space 56 to which the blower 21 delivers the air from the inlet duct 18. Operation of the blowers with the apparatus as disposed in FIGURE 5 causes circulation of outside air through space 52 to outlet duct 32 thereby removing heat energy from the compressor and condenser to the outside air at a relatively high rate as a result of the high rate of air flow developed by blower 22. The room air brought in through inlet duct 18 by blower 21 is passed through evaporator 40 and redelivered to the room 17 through the outlet duct 30 at a lowered temperature, thereby cooling room 17 while yet permitting the volume of the circulated air to be a relatively low volume. As shown in FIGURE 5 in this arrangement, the dividing wall 39 is again sealingly connected to the front and rear walls 53 and 54 of the enclosure 13, evaporator 40 has its opposite ends sealingly connected to the right side wall 26 by the connector 45, and the condenser has its opposite ends sealingly connected to the left side wall 28 by the connector 46 thereby efficiently isolating the two air flows through the apparatus and maintaining maximum efficiency of heat transfer therein.

Referring now to FIGURE 6, the apparatus 10 may be arranged to provide a removal of room air to the outside space and a delivery of outside air to the room for ventilating the room space as desired. More specifically, in this arrangement the platform 33 is rotated degrees in a counterclockwise direction from the position of FIGURE 4 to the position of FIGURE 6. In this arrangement, the outside air flowed by blower 22 is delivered to the rear portion 52a of space 52. Dividing wall 39 extends parallel to rear wall 53 and front wall 54 so as to prevent fiow to the front portion 52b of lefthand space 52, and directs the air flow to the rear portion 56a of right-hand space 56. Flow of the air from blower 22 to the left from space portion 52a into outlet duct 32 is prevented by the extension of wall 38 from connector 46 to the dividing wall 39 and, thus, the air is directed outwardly to the right as seen in FIGURE 6 through the opening 43 between the counter clockwise end of evaporator 42 and dividing wall 39 through the opening 27 in housing wall 26 and through outlet duct 30 to the room 17. Concurrently therewith, blower 21 delivers air from the inlet duct 18 into the forward portion 56b of right-hand space 56. The wall 37 extending between the connector 45 and dividing wall 39 precludes movement of this air to the right, as seen in FIGURE 6, into the outlet duct 30 and, thus, the air is conducted from space 56b to the left through space 52b and outwardly through the opening 41 between the counterclockwise end of evaporator 46 and dividing wall 39 to pass through opening 29 to outlet duct 32 for delivery to the outside. As the rate of air flow from the outside into room 17 etfected by blower 22 is greater than the rate of air flow efi'ected by blower 21 in removing air from room 17 to the outside, a slight positive pressure may be effected in the room 17 thereby further facititating the ventilation thereof.

The blowers 21 and 22 may be individually operated in lieu of the concurrent operation as discussed above, as desired. Thus, ventilation of the room space 17 may be effected solely by operation of the blower 21 to exhaust the room air without bringing in outside air by means of blower 22. Alternatively, blower 22 may be operated while blower 21 is allowed to remain inoperative, whereby outside air is delivered to the room space 17 without concurrent exhausting of the room air through the apparatus 10. Such single motor operation of the apparatus may be provided, for example, when a cross ventilation of the room space is desired such as by providing air delivery or exhaust means at a point remote to the apparatus 10, e.g. an open window in a portion of the room spaced from the apparatus.

By rotating the platform 33 to a position intermediate that of FIGURES 4 and 6, ventilation of the room space 17 may be effected by means of tempered air such as where the outside air is relatively cold and it is desired to warm the air somewhat before delivering it into the room. Thus, as shown in FIGURE 7, the apparatus 10 may be arranged to dispose condenser 42 with the clockwise end thereof extending partially across opening 27 so that a portion of the air delivered by blower 22 into space portion 52a and thence through space portion 56:: to outlet duct 30 is caused to pass through the condenser 42 thereby warming a portion of the air. At the same time, a portion of the air delivered to space portion 56b by blower 21 and thence through space portion 52b is passed through the counterclockwise end of the evaporator 40 in flowing outwardly through opening 29 to outlet duct 32 thereby transferring heat energy therebetween for improved efiiciency of operation of the apparatus.

In the arrangement of FIGURE 7, the wall 38 is in sealing engagement with the connector 46 mid-way between the condenser 42 and dividing wall 39 and wall 37 is in sealing engagement with connector 45 mid-Way between evaporator 40 and dividing wall 39 to preclude undesirable mixing of the air flows provided by the blowers 21 and 22. In the arrangement of FIGURE 7, the location of the compressor on the platform provides for further Warming of the air delivered to the outlet duct 30 further improving efliciency of the operation of the apparatus.

It is obvious that a 180 degree reversal of the arrangement of FIGURE 7 so as to interchange the positioning of evaporato 40 and condenser 42 may be effected if desired to provide a slight cooling of the air delivered from the outside to room 17 where a cooling tempering of the ventilation air is desired.

As shown in FIGURE 2, the upper housing enclosure 12 includes a selectively positionable wall panel 58 arranged to close the top of first blower space 15, as shown in full lines in FIGURE 2, or the side of the first blower space 15, as shown in dotted lines in FIGURE 2. Thus, where the inlet duct 18 extends vertically to the housing 12, the wall member 58 may be installed in the dotted line position with the air entering the blower space 15 through the now open upper end of the space from the duct 18. Similarly, the housing may further include a selectively positionable wall member 59 for alternatively closing the upper end of second blower space 16 or the side thereof as shown respectively in full lines and dotted lines in FIGURE 2. Thus, the apparatus 10 is adapted for facilitated installation in association with existing duct work and further permits improved flexibility in the arrangement of the duct work where the entire installation is new.

Apparatus 10 provides a still further highly desirable feature in the provision of the housing 12 and the blowers 21 and 22 therein as a unit separable from the lower enclosure 13 and the apparatus installed therein. More specifically, as shown in FIGURE 2, the bottom wall 24 of the enclosure 12 may be secured to the lower enclosure or housing 13 by suitable brackets 69 and screws 61 at the upper ends of the side walls 26 and 28, respectively. Thus, the upper and lower portions of the up paratus 10 may be shipped and handled separately as during installation. More specifically, the size of the respective upper and lower portions of the apparatus 10 may be preselected to permit facilitated movement thereof through conventional door openings such as the conventional 30-inch wide door openings, while yet the over-all dimensions of the apparatus 10 may exceed the normal door opening widths. Still further, the separability of the housing, or enclosure portions of the apparatus permits for facilitated subsequent maintenance.

Thus, apparatus 10 provides for improved etficient balanced air flow with air recirculation to the room being selectively refrigerated or warmed, and with ventilation of the room as by outside air delivery thereto being sub stantially at the temperature of the outside air or tempered by warming or cooling thereof as desired. By simple rotation of the platform supporting the heat transfer elements of the apparatus for selective dispositioning thereof relative to the air moving means, a simple and economical construction is obtained. providing the above highly desirable operation in a novel and simple manner. Further, installation and maintenance are substantially simplified and facilitated, as discussed above.

While I have shown and described one embodiment of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as defined in the appended claims.

The embodiment of the invention in which an exclusive property or privilege is claimed is defined as follows:

1. Apparatus for providing conditioned air to a chamber, comprising:

heat transfer apparatus including an endothermic portion and an exothermic portion;

means defining a heat transfer space including first and second portions;

means for disposing said heat transfer apparatus with said endothermic portion and exothermic portion selectively in said first and second portions of said space respectively, and in said second and first portions of said space respectively;

first means for flowing air from said chamber to said first portion of said space; second means for flowing air from externally of said chamber to said second portion of said space, said second air flowing means being arranged to flow air at a rate substantially greater than the rate at which said first air flowing means flows air; and

means for conducting air in heat exchange relationship with said heat transfer apparatus from said first portion of said space to said chamber, and

from said second portion of said space to externally of said chamber.

2. The apparatus of claim 1 further including means for operating said air flowing means to flow air selectively solely from said chamber to externally thereof.

3. The apparatus of claim 1 further including means for operating said air flowing means to flow air selectively solely from externally of said chamber to said chamber.

4. The apparatus of claim 1 wherein said rate of flow of said second air flowing means is approximately 70 percent greater than the rate of flow of said first air flowing means.

5. Apparatus for providing conditioned air to chamber, comprising:

heat transfer apparatus including an endothermic portion and an exothermic portion;

means defining a heat transfer space including first and second portions;

means for disposing said heat transfer apparatus with said endothermic portion and exothermic portion selectively in said first and second portion of said space respectively, in said second and first portion of said space respectively, and concurrently partially in each of said portions of said space;

first means for flowing air from said chamber to said first portion of said space;

second means for flowing air from externally of said chamber to said second portion of said space, said second air flowing means being arranged to flow air at a rate substantially greater than the rate at which said first air flowing means flows air; and

means for conducting air in heat exchange relationship with said heat transfer apparatus from said first portion of said space to said chamber, and from said second portion of said space to externally of said chamber.

6. Apparatus for providing conditioned air to a chamber, comprising:

heat transfer apparatus including an endothermic portion and an exothermic portion;

means defining a heat transfer space including first and second portions;

means for disposing said heat transfer apparatus with said endothermic portion and exothermic portion selectively in said first and second portions of said space respectively, in said second and first portions of said space respectively, and concurrently partially in each of said portions of said space;

first means for flowing air from said chamber to said first portion of said space;

second means for flowing air from externally of said chamber to said second portion of said space, said second air flowing means being arranged to flow air at a rate substantially greater than the rate at which said first air flowing means flows air; and

means for conducting air from said first portion of said space to said chamber, and

from said second portion of said space to externally of said chamber,

said disposing means disposing said heat transfer apparatus selectively for heat exchange relationship with said air in said space and substantially free of heat exchange relationship therewith.

7. Apparatus for providing conditioned air to a chamber, comprising:

heat transfer apparatus including an endothermic portion and an exothermic portion;

means defining a heat transfer space including first and second portions;

means for disposing said heat transfer apparatus with said endothermic portion and exothermic portion selectively in said first and second portions of said space respectively in said second and first portions of said space respectively, and

concurrently partially in each of said portions of said space;

first means for flowing air from said chamber to said first portion of said space;

second means for flowing air from externally of said chamber to said second portion of said space, said second air flowing means being arranged to flow air at a rate substantially greater than the rate at which said first air flowing means flows air; and

means for conducting air selectively from said first portion of said space to said chamher, from said second portion of said space to externally of said chamber, from said first portion of said space through said second portion of said space to externally of said chamber, and from said second portion of said space through said first portion of said space to said chamber, said disposing means disposing said heat transfer apparatus selectively for heat exchange relationship with said air in said space and substantially free of heat exchange relationship therewith.

8. Apparatus for providing conditioned air to a chamber, comprising:

heat transfer apparatus including a condenser and an evaporator;

means defining a heat transfer space including first and second portions;

means for selectively disposing said heat transfer apparatus with said condenser and evaporator in said first and second portions of said space respectively,

in said second and first portions of said space respectively, and

concurrently partially in each of said portions of said space;

a first blower for flowing air fromsaid chamber to said first portion of said space;

a second blower for flowing air from externally of said chamber to said second portion of said space, said second blower being arranged to flow air at a rate substantially greater than the rate at which said first blower flows air; and

means for conducting air in heat exchange relationship with said heat transfer apparatus from said first portion of said space to said chamber, and

from said second portion of said space to externally of said chamber.

9. The apparatus of claim 8 including a rotatable platform, said condenser and evaporator being carried by said platform.

10. Apparatus for providing conditioned air to a chamber, comprising:

heat transfer apparatus including an endothermic portion and an exothermic portion;

means defining a heat transfer space including first and second portions;

means for disposing said heat transfer apparatus with said endothermic portion and exothermic portion selectively in said first and second portions of said space re spectively, and

in said second and first portions of said space respectively; first means for flowing air from said chamber to said first portion of said space; second means for flowing air from externally of said chamber to said second portion of said space, said second air flowing means being arranged to flow air at a rate substantially greater than the rate at which said first air flowing means flows air; means for conducting air in heat exchange relationship with said heat transfer apparatus from said first portion of said space to said chamber, and from said second portion of said space to externally of said chamber; and means for removably securing said first and second air flowing means as a unit to said means defining the heat transfer space. 11. Apparatus for providing conditioned air to a chamber, comprising:

heat transfer apparatus including an endothermic portion and an exothermic portion; means defining a heat transfer space including first and second portions; means for disposing said heat transfer apparatus with said endothermic portion and exothermic portion selectively in said first and second portions of said space respectively, and in said second and first portions of said space respectively;

air flowing means including a housing, first means in said housing for flowing air from said chamber to said first portion of said space and second means in said housing for flowing air from externally of said chamber to said second portion of said space, said housing having means for providing a selectively positionable opening providing communication between said chamber and selectively either of said space portions; and

means for conducting air in heat exchange relationship with said heat transfer apparatus from said first portion of said space to said chamber, and from said second portion of said space to externally of said chamber,

said housing defining a top and a side, and said opening means being selectively positionable to provide said opening alternatively in said top or said side.

References Cited UNITED STATES PATENTS WILLIAM J. WYE, Primary Examiner. 

1. APPARATUS FOR PROVIDING CONDITIONED AIR TO A CHAMBER, COMPRISING: HEAT TRANSFER APPARATUS INCLUDING AN ENDOTHERMIC PORTION AND AN EXOTHERMIC PORTION; MEANS DEFINING A HEAT TRANSFER SPACE INDLUDING FIRST AND SECOND PORTIONS; MEANS FOR DISPOSING SAID HEAT TRANSFER APPARATUS WITH SAID ENDOTHERMIC PORTION AND EXOTHERMIC PORTION SELECTIVELY IN SAID FIRST AND SECOND PORTIONS OF SAID SPACE RESPECTIVELY, AND IN SAID SECOND AND FIRST PORTIONS OF SAID SPACE RESPECTIVELY; FIRST MEANS FOR FLOWING AIR FROM SAID CHAMBER TO SAID FIRST PORTION OF SAID SPACE; SECOND MEANS FOR FLOWING AIR FROM EXTERNALLY OF SAID CHAMBER TO SAID SECOND PORTION OF SAID SPACE, SAID SECOND AIR FLOWING MEANS BEING ARRANGED TO FLOW AIR AT A RATE SUBSTANTIALLY GREATER THAN THE RATE AT WHICH SAID FIRST AIR FLOWING MEANS FLOWS AIR; AND MEANS FOR CONDUCTING AIR IN HEAT EXCHANGE RELATIONSHIP WITH SAID HEAT TRANSFER APPARATUS FROM SAID FIRST PORTION OF SAID SPACE TO SAID CHAMBER, AND FROM SAID SECOND PORTION OF SAID SPACE OF EXTERNALLY OF SAID CHAMBER. 